Certain surgical procedures require bones to be cut at precise angles. For example, the Austin, or Chevron, bunionectomy requires the medical professional to make a precise sixty degree angled cut into the first metatarsal head so that the two resulting metatarsal sections can be translated sideways and affixed together. Likewise, in knee replacement surgery, the lower end of the femur must be cut to match the shape of the particular knee replacement implant that will be used.
In a typical knee replacement procedure, the femur is shaped by making a series of cuts with a single-bladed surgical saw. A cutting guide is used to help the surgeon make the appropriately angled cuts. The cutting guide is pinned in place on the femur and the saw is used to make the first cut. The cutting guide is then repositioned on the femur and the saw is used to make the second cut. These repositioning and cutting steps are performed sequentially until all of the necessary cuts are complete.
Although the conventional knee replacement procedure works well, it is inefficient and more complicated than it needs to be.